The existing vapor pressure measurements reported in the literature for parahydrogen between the triple point and the critical point have been employed to establish the constants and exponent of the following equation in the form of reduced vapor pressure and reduced temperature: ln = 2.64 - $＼frac{2.75}{}$ + 1.48129 ln + 0.11 Only the normal boiling point (= 20.268K), the critical pressure (= 1292.81 kPa), and the critical temperature (= 32.976K) are necessary to calculate the vapor pressure for an overall average deviation of 0.21% for 153 experimental vapor pressure data.

The trace-level mercury in bio-materials has been determinated by the anodic stripping square wave voltammetry (ASSWV)-technique at glassy carbon electrode. Prior to the analysis, the bio-materials were digested with HNOH2SO4 mixture and KMnO4 was added to complete an oxidation process of the mixture. The detection limit of the mercury varied greatly with deposition time, deposition potential, pH and stirring rate. When the deposition was carried out for 240 sec on 400 rpm stirring at -1.0 volts vs. Ag/AgCl, the detection limit was below 0.5 ppb (2.5M). The accumulated mercury was high in the kidney and liver, and low in the brain according to the determination of mercury accumulation for a white rat by this method.

A study has been carried out on the extraction chromatographic separation of fission products from spent pressurized water reactor (PWR) fuels for inductively coupled plasma atomic emission spectrometric analysis. Impregnation capacity of tri-n-butyl phosphate (TBP), which is well known as an extractant in the field of uranium separation from various nuclear grade materials, on Amberlite XAD polymeric macroporous support materials was measured. Amberlite XAD-16 of which the surface area is the highest was selected as a support material because its TBP impregnation capacity was the largest in Amberlite XADs. Sorption behaviour of this TBP impregnated resin was investigated for the fission product elements using acidic solutions simulated for dissolver solutions of spent PWR fuels. The parameters affecting the performance of the separation system were optimized. The fission product elements studied excluding Pd and Ru were quantitatively recovered with the precision of less than 3.1%.

7'-Aldehyde-nucleosides analogue (2a, 2c) were synthesized from 6-N-benzoyl-2',3'-O-isopropylideneadenosine and uridine. The condensation of 2 with ethoxycarbonylmethylene Wittig reagent produced the adenosine and uridine analogues containing extended conjugated diene and ethoxycarbonyl group, ethyl-1',5',6',7',8'-pentadeoxy-1'-(adenin-9-yl)--D-ribo-nona-5'(E),7'(E)-dienofuranuronate (4b) and ethyl-1'. 5',6',7',8'-pentadeoxy-1'-(uracil-1-yl)--D-ribo-nona-5'(E),7'-(E)-dienofuranuronate (4c). 9-[8',8'-dibromo-5',6',7',8' -tetradeoxy--D-ribo-octa-5'(E),7'(E)-diene]nucleosides (6b, 6c) were also prepared from 2 with similar method.

The reaction of 6-chloro-2-hydrazinoquinoxaline(4) or 6-chloro-2-hydrazinoquinoxaline 4-oxide(7) with alkyl (ethoxymethylene)cyanoacetates gave pyrazolylquinoxalines(5, 8). The reaction of compounds 8 with dimethyl acetylenedicarboxylate resulted in the 1,3-dipolar cycloaddition reaction and then ring transformation to afford pyrazolylpyrrolo[1,2-a]quinoxalines(9).

The 4-substituted tetrazolo[1,5-a]quinoxalines were synthesized from 4-chlorotetrazolo-[1,5-a]quinoxaline(8) or 4-hydrazinotetrazolo[1,5-a]quinoxaline(9). Refluxing of the tetrazolo[1,5-a]quinoxaline(12) in N,N-dimethylformamide gave the 1,2,4-triazolo[3,4-c]tetrazolo[1,5-a]quinoxaline(13), which was also obtained by the reaction of compound 9 with ethyl chloroformate in N,N-dimethylformamide. The reaction of compound 9 with isothiocyanates in ethanol provided the tetrazolo[1,5-a]quinoxalines(14), whose reaction with dimethyl acetylenedicarboxylate afforded the tetrazolo[1,5-a]quinoxalines(15). The tetrazolo [1,5-a]quinoxalines(18) were obtained by the reaction of compound 9 with alkyl (ethoxymethylene)cyanoacetates. Some of the compounds showed antibacterial, antifungal or algicidal activities against some strains.

The water soluble carboxymethyl-chitin (CM-chitin) has been well known to be very useful to the cosmetic field as a moisturizer, a smoothener, a cell activater and a cleaner for face skin conditioning. In this study, the preparation process of CM-chitin was simplified with elimination of some procedures in the conventional method. The chitin powder was mixed with sodium hydroxide solution. And then a mixture of sodium monochloroacetate (or monochloroacetic acid) and isopropyl alcohol (or a mixed solution with water and isopropyl alcohol) was added to thorough the agitation and the freezing during 16 hours. The CM-chitin with a high degree of substitution by the improved process was obtained.

Aluminum Hydroxide was employed as a thermal retardent and flame retardent for Chloropolyethylene (CPE) rubbery materials which is the construction material of automotive oil cooler hose. and then cure characteristics, physical properties, thermal resistance and flame retardation of compounded rubber were investigated, and optimum mixing conditions of rubber and flame retarding agent were deduced from the experimental results. CPE rubber material which has excellent properties of chemical corrosion resistance and cold resistance and inexpensive in price was used to prepare rubber specimen. The by-product of ething, produced from the process of surface treatment of aluminum was processed to aluminum hydroxide via crushing and purification, which is characterized by XRD, PSA, SEM and ICP-AES techniques in terms of phase, size, distribution, morphology and components of particles and then mixed to CPE rubber materials in the range of 0~80 phr. Hardness, tensile strength, elongation and thermal properties of compounded rubber specimens were tested. The optimum mixing ratio of rubber to additives to give maximum effect on thermal resistance and flame retardation, within the range of tolerable specification for rubber materials, was determined to be 40 phr. The flame retardation of CPE rubber materials was found to be increased by 5 times at this mixing ratio.

Planarization of the free-standing diamond film surface as smooth as possible could be obtained by using the hydrogen plasma etching with the diffusion of the carbon species into the metal alloy (Fe, Cr, Ni). For this process, we placed the free-standing diamond film between the metal alloy and the Mo substrate like a metal-diamond-molybdenum (MDM) sandwich. We set the sandwich-type MDM in a microwave-plasma-enhanced chemical vapor deposition (MPECVD) system. The sandwich-type MDM was heated over ca. 1000 by using the hydrogen plasma. We call this process as the hydrogen plasma etching with carbon diffusion process. After etching the free-standing diamond film surface, we investigated surface roughness, morphologies, and the incorporated impurities on the etched diamond film surface. Finally, we suggest that the hydrogen plasma etching with carbon diffusion process is an adequate etching technique for the fabrication of the diamond film surface applicable to electronic devices.

This study aimed to analyze the evolution of general ideas concerning the element and the atom. In the scientific viewpoint, the modern idea of the element has been variously revised by the ancient Greeks, Boyle-Lavoisier, and Dalton. The definition of the atom was confused with that of the element from the ancient Greecian era to Lavoisier's era. The definition was also changed by Dalton and Rutherford. An analysis of the definitions of element and atom as presented in science textbooks for secondary school students and in general chemistry textbooks revealed that these definitions from diverse eras are confusing and inadequately explicated. The definition presented in one textbook was contradictory to the definitions in other textbooks. This tendency has been sustained in the textbooks from the 4th to 6th science curriculum. Therefore, we need to clarify the definitions of element and atom in order to help the students gain a better understanding of these scientific concepts.

In this study, high school students' problem-solving strategy-performing ability was measured by an essay-type test. The relationship between students' logical thinking ability and strategy-performing ability was also investigated. Four classes (N=187) were selected from two high schools in Seoul, and the strategy performance ability test and the Group Assessment of Logical Thinking (GALT) were administered. Evaluation scheme for strategy-performing ability consists of 7 subcategories - understanding given of problems, recalling related law, setting up subgoals, deriving physical quantities, logical progress, mathematical execution, and reviewing. The intercoder agreement for scaling was .92, which indicated substantial strength of agreement. The results revealed that students' ability of understanding given of problems and mathematical execution was relatively high. However, their ability of setting up subgoals and reviewing was very low. The total scores of the strategy performance ability test and all of the scores of each subcategory were significantly correlated with the GALT scores.